Heretofore, metal and ceramic compositions have been sintered into molded articles by processes such as compression molding. Compression molding involves the steps of drying polymeric particulates, placing the particulates into a mold, heating, applying pressure to the heated mold, reducing the pressure to atmospheric conditions, and free sintering. The process often involves repeated heating and pressure steps until the desired article density and shape are obtained followed by free sintering. This process is slow, consumes large amounts of energy and labor, and produces a limited amount of sintered articles.
U.S. Pat. Nos. 4,539,175 and 4,640,711 teach a method of consolidating objects made from metallic, metallic and ceramic composite, and ceramic compositions by employing graphite particulates. The composition to be consolidated, a powdered, sintered, fibrous, sponge or other form capable of compaction, is placed within a contained zone and around it is placed a bed of flowable, resiliently compressible carbonaceous material such as graphite. The contained zone is then heated to a temperature of about 1000.degree. to 4000.degree. C. followed by pressurization of the bed while still hot. After cooling, the consolidated object is removed from the contained zone.